The Collaborative International Dictionary of English v.0.48:

homestretch \homestretch\ n.
   1. the straight segment of a racetrack leading to the finish
      line. [WordNet sense 1]
      [WordNet 1.5]

   2. Hence: [fig.] The last or concluding part of any extended
      activity that has a definite conclusion; the final phase
      of any activity; as, the election was neck-and-neck in the
      homestretch.
      [PJC] hometown

WordNet (r) 3.0 (2006):

homestretch
    n 1: the end of an enterprise; "they were on the homestretch
         when the computer crashed"
    2: the straight stretch of a racetrack leading to the finish
       line